Scientific studies show that identical twins who were separated at birth and raised in different homes may vary in height, weight, and intelligence.
The most probable explanation for these differences is that
A) original genes of each twin increased in number as they developed.
B) environments in which they were raised were different enough to affect the expression of their genes.
C) one twin received genes only from the mother while the other twin received genes only from the father.
D) environments in which they were raised were different enough to change the genetic makeup of both individuals.